Oven heat-contkol pevice



El Ll w- El OVEN HEAT CONTROL DEVICE. APPLICATION FILED MAY 25, I92].

Patented 0ct.24, 1922.

2 SHEETS-SHEET l- INVENTOR.V

E. L. AND W. E. CLAUS.

, OVEN HEAT CONTROL DEVICE.

APPLICATION FILED MAY 25, I92l.

Patbh ted Oct. 24, 1922.

2 SHEETSSHEET 2.

llllll INVEN TOR.

Patented Oct. 24, 1922.

UNITED STATES 1,433,179 "PATENT OFFICE.

EMIL L; CLAUS AND WALTER E. CLAUS, OF'MILWAUKEE, WISCONSIN.

OVEN HEAT-CONTROL DEVICE.

Application filed May 25. 1921. Serial No. 472,610.

Devices; and we do hereby declare that the following is a full, clear, and exact descriptionthereof.

This invention relatesto certain new and useful improvements in oven heat controlling devices, in which a bimetallic strip is held substantially rigid at each end and has a valve member medially connectedthere I with whereby the resultant bowing of themember under temperature changes actuatesl the valve member and controls the oven heat.

vIn the oven heat controlling or regulating devices now generally employed there is some leakage of gas from the. valve proper where the valve stem passes outwardly therefrom, as the result of which the underwriters approval is not as readily obtained and furthermore there is a resultingwaste It is hence an ob ect of this invention to provide improved means for insurin fuel.

I ing the positive prevention of leakage past the valve member stem and the leading oil" of all gas which may tend to escape, to be consumed by a pilot light.

. In all thermostatic instruments it is essential that some play be allowed when the parts thereof are cool inorder to accommodate for the expansion of the parts when under heat, and consequently the present oven heat controlling devices have been incapable of fine adjustmentdue to this slack being en- :gagedby, one. side of the adjusting member ,when'. the temperature, adjustment: is beingajcomewithin .the scope of the-claims.

lowered and another side when the temperature is being raised resulting in avariation of..a number .otdegrees. ,.Consequently it will be. readily seen that 1 with, the slack,

which, is. absolutely necessary, it, is impossible to obtain, exact calibration and it, is

, therefore another object of thisinvention to provide means whereby .a tension .is applied at all times to the necessary slack so. that :in

,,adjustment will be made exact,

adjustingeither to or from a setpositionthe f Another objectionto a thermostatic .con-

trollingfdevice employing abi-metallic membelt, made substantially rigid at. both ends f a valve-mcmberiis, that should "the operator and; connected at an. intermediate point with and in, section,.,. .=,.;F1gure. 3 is a new part. elevation. taken. through: the. controll ng desire to advance the oven heat at first, sayv 550 degrees, and then later adjust the device for a lower temperature, 300 degrees, some compensating means must be connected with the bi-metallic member, as under the great heat the same is bowed and the adjustmentto a lower temperature will draw in the member and seat the valve and a continued adjustment will bend the member in an op- 5 posite direction. This applied extra stress to the bi-metallic member, while under heat, ;1s very liable to strain the same so that it wlli not resume its normal position when coo invention. to provide means engageable with one fastening or securing member of the bimetalhc member whereby the same will give I u i 7 Consequently it IS a further ob ect of this when the stress of adjusting the device nears the point where injury would be done the bi-metallic member.

It is still a further object of our invention to provide an improved heat regulating or controlling device of the class described,

which is capable of ready application to ovens now in use as well as to ovens at the time of theirmanufacture without in any manner marring the same and without necessitating any change whatsoever in the parts thereof.

WVith the above and other objects in view which will appear. as the description procoeds, our invention resides in the novel construction, combination and arrangement of herein rdisclosed invention may be .made .as

In the accompanying drawi-ngs,--we have .illust;rated. one. complete-example of the physical embodiment of our. invention con- .{structed according to the'best mode we have so. far devised. for"the .practical application 7 of. tllGilJPlIlClP-lGS thereon-and in' w hichz Figure vl isa perspective .viewlookingat 0116 .S1Cl6 of an oven equipped with our in :.-vention;.

@Figure isa top planview of ur imprOYed dev1ce.;the oven wall being In section v k .and parts of the device zbeinglbroken away in section, part in gmember,OnftheliIIeB B ofFigure'1.

Figure 4 is a fragmentary view of one .end

of the thermostatic member and its support, p

t Figure 5 is a fragmentary view of the opposite end of the thermostatic member and its adjustable securing member, the thermostatic member being in section, and

Figure 6 is a fragmentary view, partly in elevation and partly in section, illustrating the relative areas of the pilot supply pipe inlet and outlet. j v Referring now more particularly to the accompanying drawings in which like numerals designate like parts throughout the several views, the numeral 5 designates the of which (not shown) is su" plied with fuel heating oven of a range or stove, the burner by a pipe 6, The fuel for t e burner passes through our improved control device which is connected with the pipe 6 by a connection land with a burner by a connection 8. The

-' connection 7 has a shut-off valve or cook 9 V therein from which also leads apilotsup'ply pipe 10, the pilot supply pipe opening 11 in valve 9 being adjustable by a screw 11. The area of the opening 11' communicating with the pilot supply pipe is preferably less A than that of the outlet where the pilot is maintained, whereby the pressure within pipe 10 is atmospheric for the reasons hereinafter set forth. I j The control device consists of avalve casing or body 12, which may be either in the form of an L (as shown) or a straight coupling provided with an inlet 13 wlth which connection 7 is coupled'and an outletendl l with which connection 8 is coupled.

The inletand outlet are separated by a partition within the valve casing which is centrally bored or 'apertured to provide a fuel passage-way or port 15 formed with a valve seat 16. One wall of the body 12 is bored concentric with the valve seat 16 and is internally threaded to receive' a oap or plug 17.

The valve member 18 is adapted to engage seat 16and has a stem 19 which passes out wardly through a bore 20in cap 17. The

1 stem 19 has a substantially snu able fit in bore 20 whereby to eliminate as much aspossible all leakage from the interior of the valve casing around said stem.

However, in order to prevent the escapage 'of any gas ,whatsoeveninto the interior vide a pocket or intermediate chamber21 in.

I so

of the oven past the valve stem, (the bore 20 is medially recessed or counterboredtorprowhich such leakage expands. The plug 17 has its outer wall annually groovedias at passages 23 into the chamber or channel 22 pressure, ashereinbefore described.

ing diametrically opposed arms 32 and described.

conducting ocket. v, i it Any fluid leaking from the interior of the valve casing around the stem 19 ex pands in the pocket 21, then escapes through and then through pipe 25 into the pilot supply pipe 10 where the leakage is economically used in supplying fuel to the pilot (not shown). Back pressure inpipe 25 is prevented by reason of the pilot opening 10 being of greater area than the inlet openany leaking fluid from the ing' 11' to thus maintain the pressure within p'pf-lO equal to or lower than atmospheric v That portion of body 12 surrounding the bore in which plug 17 is secured is laterally flanged, as at 26, to provide means for attaching the device to the oven wall 5?. y *In" Y attaching the devicefthe oven wall 5 is "cutaway as at 27 at'the point where it is desired to locate the "deviceyand the .valve I body 12 is clamped to the wall by fastening members 28 which pass through apertures in the flange 26, through apertures in wall 5" andthrough a bracket member or sup porting plate 29, a PlateBOfbein'g-J secured between the wall 5i and the flange 26'to serve as a filler andto carr the setting dial" 31 to be hereinafter described.

The bracket member or supporting plate 29 is provided with two laterally extend the arIn1 32 having a lug or projection 34 formedat its outer end and the arm a centrally bored lug or projection 35 which projects in an oppositedirection to lug-[34,

and is positioned exteriorly of the oven wall 5through an opening therein. The lug 35" has its end positioned outwardly of theoven away from the influence of the heat internally threaded to receive a setting screw 36. "The extreme inner end of the setting screw 36is cut away or reduced as at 37, to per- 1 ma the attachment thereto of one'end of. a strip of material. 38-which. issensitive to temperature changes, screw '36 providing means for setting and ad usting strip 38.

The other end of said strip is secured to v projection 40 by the means new aboutjtobe The lug orprojection is centrally apertured as at 39 in alinement with'registering apertures"in thejoven wall 5 and plate30 7 "to receive the stem aOof'afispindle formed with an enlarged head .41 'which overlaps the adjacent end of strip 38. "The spindle 40 normallysecuresfthe end offithematerial' engaged thereby firm against the proj ect ion v 34: by means ofia cone-shaped spiral spring 42 coiled about the outer ends of the stem 40 and confined between-the plate 30 and 'a removable nut"43. The strip 38- is retained in engagement with head 41 by two spaced ears or guide means 44 between which the adjacent strip end is positioned, this constructlon provldlng compensating means whlch come into play more especially when .the oven is at a high heat and the operator jected to heat due to one metal comprising "the same expanding more than the other.

The bracket member 29 is centrally apertured as at to accommodate the head of cap 17 and the inner end 46 of the valve stem 19 is threaded and passes into the interior of the oven through said aperture. The member 38 is provided with central aperture 4-7 through which the valve stem end 46 passesiand .said member is adjustably made fast to the stem by knurled nuts d8 engaging the:oppositesides of the strip. By this construction, flexing or bending of strip 38, due to the expanding thereof as hereinbefore stated, will transmit a corresponding movement to the valve 18, however slight.

In the present embodiment the side of the stem 38, formed of "the material having the greater degree of expansibility, is placed nearest the oven wall of5 so that, upon expansion, the medial portion of said memher will be bowed theretowa-rd to move the valve toward seating position, however, it will be readily appreciated that this action may be reversed according to the designof the control valve. 1 In all thermostatic instrumentsit is necessary that some slack orplaybe allowed when thepartsare cool in order that, when subjected to heat, the parts will not become bound, due to unequal expansion. Conse quently, it will be readily appreciated that the point of connection between the strip 38 and the setting screw 36, as well as any other connection, ispreferably substantially "loos rid; 'as' 1a result, in s ren ths instru- "meat, as Will be he smar er ,describe d, this slack reps one side w en setting the instruinent for afhighefde gr'ee "ofternpe'rature, and oiiithe other when setting the instrument jfora'i we ofteinperaturef As a r s'hlt of this, accurate calibration is impos- :SlljlG and we sarcoma "ems; serious fault by es e pri gs 9 l i a fit l s er'ri1'9' and confined between the inner most all times tends to urge the inner most nut 48, against the inner face fof thestrip 38 thtis' pro" "idi'iiga tensionwhich retains the sla cl' 1*" 1ay'a1ways toone eraser the peat e "or the manner" in which i As often times it is desirable to retain a "parts' are low flame at the burner, a set screw 50 is adjustably secured-in an internally threaded bore 51 of the valve casing and has its 1111181 end positioned concentric with respect to the valve seat 16. The bore 51 is, surrounded by a boss 52 normally enclosed by a removable cap 53. As Wlll be readily ap:

parent the set screw 50 may be adjusted tov permit fuli'seating of the valve 18 or to prevent the seating thereof to any desired degree. The-pl,ate 30 has its end 54 ape-rtured to register with the aperture through which the projection 35 of the bracket member passes and is provided with a laterally projected flange, not shown) to which the dial 31 is secured by fast nings 55, the dial 31 preferably being inclined at a substantially 45 degree angle with respect'to the perpendicular to permit reading thereof.

The dial 31 is provided with suitable gradua- I 1Z1OHS or various degrees of temperature and carries a medially pivoted pointer or indicator 56 which is connected with a collar 57, adjustably secured to the setting screw 36.

With the oven cold, and the thermostatic member substantially straight, handle 58 is rotated to register indicator 56 with the temperature at which it is desired to maintain the oven and the [greater the heat desired the further into the oven is positioned that endv of member 38 connected with screw 36. As the oven temperature increasesfthe medial portion of member 38 bows inwardly, by reason of'that side thereof formed of the metal having the highest coeflicient of expansion being nearest the oven wall, and valve 18 is consequently moved toward closed position.-

lVhen the oven has reached the desired tenriperature. valve 18 abuts stop 50 and only a minimum flame is maintained at the burner, and as the oven temperature falls below the set degree, member 38 straightens, opening valve 18 to increase the flame of the burner.

Should the operator setthe oven for a high-temperature and then,*after strip 38 is ;ceneidembi bo ease; the oven for 'a'low'er temperature, the compensating means here-- inbe'fore illustrate'd prevents 'straining'fof f strip 38, shouldiscrew 36"be moved outwardly sufficientto engage valve 18 with stop 50 unnaturally bend the thermo'sflitic member. (What we claim is'z' f; lfiln a thermo-contr'ol device, afm'einb'er sensitive to temperaturechange ,jnea'ns curing said memberfivliereby the same will bow when heated, valve" ineansfconnected straining,ofsaid member in setting is prevented.

2. In a thermo-control device, a member sensitive totemperature changes, means securing opposite end portions of said member,

the means securing one end portion being transversely yieldable upon stress. on said member reaching a predetermined limit, and a heat controlling member connected with said first mentioned member;

3. In a thermo-control device of the class dBSCIIbGCl, a supporting plate, a member sensitive to temperature changes, means securing the ends of said member to said plate against longitudinal movement, one end described, a supporting plate, a member sen- 'sitive to temperature changes, means securing the endp'ortions of .sa1d membertothe plate, one end thereof .1 being transversely yieldable' underfexcessive stress and" the other ,end' thereof being adjustable, and means connectingsaid member with a temperature controlling device.

, In a Vthermo-control device of the class described, a supportingplate, member sensitive to temperature changes, means normally rigidly securing one end of said member to the platefsaid means being transversely yieldable upon the stress on said member reaching a predetermined limit, and means connecting the medial portion of said member with a temperature controlling device. i

i 6. In a thermo-c ontrol device of the class described,,a supporting plate, amember sensitiveto temperature changes, means securing one end of said member to said plate,

guide means engageable with the other end of said member, and securing means engageable with the other end of said plate and permitting transverse movement thereof upon the stress on said member reaching a predetermined limit. i

7. In athermo-control device, a member sensitiveto temperature changes, means securing said member whereby the same will bow when subje'ctedto a temperature change, said securing means preferably having some play to accommodate for the expansion of the member when subjected to heat, a heat controlling member, and a connectionbetween said members, said connection including tension means for at all times taking u theplay between the parts. i t I 8. In a thermo-control device, a member sensitive to temperature changes, means securing said member whereby the same will bowwhensubjected to a temperaturechange, said securing means preferably having slight play to accoImnodate-for the expansion of the parts whensubjeeted to. heat, a heat controlling member directly. connected withsaid first mentionedme'mber at an intermediate point, means for adjustingthe actuation of said heat controlling member by said first mentioned member, and meansfor at all times applying a tension to one side of said first mentioned member to accommodate the play between the parts. Y i 9. In a device of the class described,-a valve casing, a valve seat in saidcasing in axial alinement with an opening (in said casing, a centrally bored plug engageable in said openin a valve member engageable with said casing seat and having afistem slidably mounted in said plug bore, said plug bore having an intermediate counter ,bore, and a passage leadingfrom said coun- I terb'ore whereby leakage from the. valve casing'by the valve stemjwill, upon entering said counter-bore, expand and pass out through said passage. 10. In a device of the class described, a valve. casing, a valve seat in said caslng in axial alinement. with an opening in said casing, a centrally bored plug engageable inv said opening, a valve member engageable with said casing seat and having a stem slidably mounted in said plug bore, an intermediate. chamber communicating With said bore, an 1 outer annular chamber formed by a groove, in its outerperiphery, passages connecting said chambers, any leakage of fluid from said valve casing by the valve stem expanding in the first mentioned chamber and then passing into said second chamber, and means for conducting said fluid from said last mentioned chamber.

11. In a device of theclass described, a fuel supply pipe, a fuel control member in said pipe and including a valve casing, a

valve member in said casingand having a stem passed outwardly ofthe casingthrough a bore therein and a pocket surrounding said stem at an intermediate point of said stem whereby fluid escaping from the valve casing around saidstem willexpand in said pocket, and means'for conducting fluid from said pocket. p p

12. In a device of the class described,.:a' fuel supply pipe, afueljcontrol member in said pipe and including "a Valve casing, a

valve member in said casing andlhaving a stem passedoutwardly of the casing through a bore therein and a pocket surrounding said stem at an intermediate pointof said Stem whereby fluid escaping fromthe valve casing around said stem will expand in said pocket, a pilot supply pipe leading from said first mentioned supply p1pe, and means for conducting fluidgfrom said pocket. to the pilot supply pipe. 13, In a device'of the class described, a fuel supply pipe, a fuel control member in said p1pe and including a valve casing, a

valve member in said casingand having a stem passed outwardly of the casing through a bore therein and a pocket Surrounding said stem at an intermediate point of said stem whereby fluid escaping from the valve casing around said stem will expand in said pocket, a pilot supply pipe leading from said first mentioned supply pipe, the area of the opening connecting the first mentioned pipe and the; pilot supply pipe being less than the area of said pilot pipe. outlet whereby the pressure within the pilot pipe is substantially atmospheric, and means for conducting fluid from said pocket to the pilot pipe.

14:.v In a thermo control device, a supporting plate, a member sensitive to temperature changes, means securing the ends of said member to said plate whereby the medial portion of the same will bow when subjected'to a temperature change, one of said securing means being in the form of an adjustable element whereby the end of said member may be adjusted toward and away from the supporting plate, and said means preferably having slight play to aCoommO ber medially connected with said temperature sensit've member whereby bowing of the first mentioned member under temperature changes will actuate the heat controlling member, and means for applying a tension to one side of the temperature sensitive member whereby the play between the parts will at all times be to one side thereof.

In testimony that we claim the foregoing we have hereunto set our hands at Milwaukee, in the county of Milwaukee and State of Wisconsin.

EMIL L. OLAUS. WALTER E. CLAUS. 

